My wordpress site displays some random cassino link

For some time now, whenever I visit my site from a different browser or computer. I notice that it show’s some casino link at the head section. My site has no link whatsoever to any casino stuff and so I don’t even know how this link got to display in my site. I really want this to be removed urgently.I’ve disabled my Google translator plugin but the problem still persists.Please, What should I do????